Item 24 — Colon Breakwater. The low cost for the quarter is due to the return to the storehouse of piling and timber, which had been previously charged to the work,
but not used.

Item 28 — Dredging Excavation, prism. Preliminary surveys.

Item 32 — Dredging Excavation, prism. With the accounts for the month of April, the total cost of the dredging plant had been absorbed into the work; hence
no arbitrary for plant is charged in this quarter.

Items 53, 54, and 55. These expenditures were incurred prior to the adoption of Miraflores as the site for the lower locks and dams, at the Pacific entrance of the
Canal.

Items 25, 30, an:l 57 — Plant. The expenditures for plant and equipment are absorbed into construction costs on the basis of estimated total cost of plant, and
the estimated quantities of work to be done. The amount under these items represent the balances which are to be absorbed into construction costs after June 30, 1911.

General — When excavated material is used in filling, such as dams, back filling, etc., the cost of dumping only is charged to the items benefited, all other expenses
being charged to "excavation."

*Credit under trestles in May is due to material, already charged into the work, being returned to Quartermaster's Department. This was done in order to
determine the actual cost to May 31, 1911.
flndicates credit.